xref: /freebsd/sys/compat/linuxkpi/common/include/linux/radix-tree.h (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * Copyright (c) 2010 Isilon Systems, Inc.
3  * Copyright (c) 2010 iX Systems, Inc.
4  * Copyright (c) 2010 Panasas, Inc.
5  * Copyright (c) 2013-2018 Mellanox Technologies, Ltd.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice unmodified, this list of conditions, and the following
13  *    disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 #ifndef	_LINUXKPI_LINUX_RADIX_TREE_H_
30 #define	_LINUXKPI_LINUX_RADIX_TREE_H_
31 
32 #include <linux/types.h>
33 
34 #define	RADIX_TREE_MAP_SHIFT	6
35 #define	RADIX_TREE_MAP_SIZE	(1UL << RADIX_TREE_MAP_SHIFT)
36 #define	RADIX_TREE_MAP_MASK	(RADIX_TREE_MAP_SIZE - 1UL)
37 #define	RADIX_TREE_MAX_HEIGHT \
38 	howmany(sizeof(long) * NBBY, RADIX_TREE_MAP_SHIFT)
39 
40 #define	RADIX_TREE_ENTRY_MASK 3UL
41 #define	RADIX_TREE_EXCEPTIONAL_ENTRY 2UL
42 #define	RADIX_TREE_EXCEPTIONAL_SHIFT 2
43 
44 struct radix_tree_node {
45 	void		*slots[RADIX_TREE_MAP_SIZE];
46 	int		count;
47 };
48 
49 struct radix_tree_root {
50 	struct radix_tree_node	*rnode;
51 	gfp_t			gfp_mask;
52 	int			height;
53 };
54 
55 struct radix_tree_iter {
56 	unsigned long index;
57 };
58 
59 #define	RADIX_TREE_INIT(mask)						\
60 	    { .rnode = NULL, .gfp_mask = mask, .height = 0 };
61 #define	INIT_RADIX_TREE(root, mask)					\
62 	    { (root)->rnode = NULL; (root)->gfp_mask = mask; (root)->height = 0; }
63 #define	RADIX_TREE(name, mask)						\
64 	    struct radix_tree_root name = RADIX_TREE_INIT(mask)
65 
66 #define	radix_tree_for_each_slot(slot, root, iter, start) \
67 	for ((iter)->index = (start);			  \
68 	     radix_tree_iter_find(root, iter, &(slot)); (iter)->index++)
69 
70 static inline int
71 radix_tree_exception(void *arg)
72 {
73 	return ((uintptr_t)arg & RADIX_TREE_ENTRY_MASK);
74 }
75 
76 void	*radix_tree_lookup(struct radix_tree_root *, unsigned long);
77 void	*radix_tree_delete(struct radix_tree_root *, unsigned long);
78 int	radix_tree_insert(struct radix_tree_root *, unsigned long, void *);
79 int	radix_tree_store(struct radix_tree_root *, unsigned long, void **);
80 bool	radix_tree_iter_find(struct radix_tree_root *, struct radix_tree_iter *, void ***);
81 void	radix_tree_iter_delete(struct radix_tree_root *, struct radix_tree_iter *, void **);
82 
83 #endif	/* _LINUXKPI_LINUX_RADIX_TREE_H_ */
84